None.
Not applicable.
1. Field of the Invention
The preferred embodiments of the present invention relate generally to electrical power cords. More particularly, the preferred embodiments relate to a sealing cap for the end of an electrical power cord. More particularly still, the preferred embodiments relate to a moisture-resistant corrosion-inhibiting threaded sealing cap for use with an onshore power cord in marine applications.
2. Background of the Invention
When docked, a marine vessel generally requires a source of electricity other than its own batteries in order to enable operation of electrical appliances onboard without depleting the batteries. Electrical power is typically provided from an onshore power supply to a receptacle on the boat via a marine power cord. However, marine power cords are prone to wetness and resultant corrosion due to the risk of precipitation and proximity to water.
Preventing moisture from contacting the electrical connections, including the receptacles and terminal end of the power cord, is of utmost importance. Salt water is especially damaging to electrical connections, as dissolved salt increases the conductivity of the aqueous solution formed at the surface of a metal and enhances the rate of electrochemical corrosion. In addition, using a wet power cord is dangerous due to the risk of electrical shock or shorting. If moisture were to enter the connection when electricity is flowing, the connection could short out, potentially tripping the breaker of the onshore power supply.
Many boaters cover the ends of marine power cords by placing a plastic bag over the terminal end and securing the end of the bag to the cord with a rubber band or twist tie. Although this method largely prevents moisture intrusion, a bag is not always handy and is not quickly and easily installed and removed. In addition, this method does nothing to prevent corrosion due to humidity build-up or small amounts of moisture. Moreover, this method does not structurally protect the terminal end from mechanical damage, such as being stepped on or crushed by equipment, which could occur if left unprotected.
There have been attempts in the related art to slow corrosion in electrical connectors. For example, U.S. Pat. No. 3,372,361 to Wengen appears to disclose the use of a corrosion inhibitor in gel form within a cavity where two dissimilar metals meet. Likewise, U.S. Pat. No. 5,844,021 to Koblitz discloses a corrosion inhibitor in a gel form in the Koblitz connectors. Each of Wengen and Koblitz may be characterized in that the corrosion inhibitor must be in contact with the conductors where the anti-corrosion properties are desired. U.S. Pat. No. 6,300,574 to Franey discloses an electrical cap that contains sacrificial metals with which corrosives react, thus protecting to some extent remaining electrical components within the cap.
The Wengen and Koblitz techniques, utilizing a gel, are simply not suitable for use in marine power cord and related applications. The Franey technique of placing sacrificial metals within the polymer cap is only a passive technique, and thus may not provide sufficient protection in corrosive environments, such as marine applications.
Thus, what is needed in the art is a cap for electrical connectors, such as marine power cords, that is convenient to use, that is not easy to lose, and that more aggressively protects the electrical connectors within the power cord from corrosion.
The problems noted above are solved in large part by a cap and related method for sealing the terminal end of a marine power cord against moisture. More particularly, the preferred embodiments are directed to a cap that seals the terminal end of a marine power cord against dirt and moisture, and where the cap inhibits corrosion of the electrical connections. The preferred embodiments relate to a positively buoyant plastic cap having a threaded section for mating to a corresponding section on the terminal end of a power cord, forming a moisture-proof seal. The preferred embodiments also comprise a corrosion-inhibiting compound dispersed within the plastic material of the cap. An alternate embodiment includes a cap having a corrosion-inhibiting compound integrally dispersed within a plastic insert coupled inside the cap. The corrosion-inhibiting compound is released from the composite plastic cap, or composite plastic insert, in gaseous form actively preventing corrosion of the electrical contacts of the power cord.
The disclosed devices and methods comprise a combination of features and advantages which enable it to overcome the deficiencies of the prior art. The various characteristics described above, as well as other features, will be readily apparent to those skilled in the art upon reading the following detailed description, and by referring to the accompanying drawings.
For a detailed description of the preferred embodiments of the invention, reference will made to the accompanying drawings in which:
FIG. 1A shows an elevation view of an embodiment engaged with the terminal end of a conventional power cord;
FIG. 1B shows an embodiment of the present invention disengaged from the terminal end of a conventional power cord;
FIG. 2A shows a top view of an embodiment of the present invention;
FIG. 2B shows a sectional view of an embodiment of the present invention;
FIG. 3A shows an elevation view of an alternate embodiment engaged with the terminal end of a conventional power cord;
FIG. 3B shows an alternate embodiment disengaged from the terminal end of a conventional power cord;
FIG. 4A shows a bottom view of an alternate embodiment of the present invention; and
FIG. 4B sectional view of an alternate embodiment.